Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, Barcelona, Spain; Enza Zaden Spain R & D (04710), Sta Mª del Aguila, Almeria, Spain.
Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universidad Politécnica de Valencia (UPV), Consejo Superior de Investigaciones Científicas (CSIC), Ingeniero Fausto Elio, 46022 Valencia, Spain.
Plant Physiol Biochem. 2017 Dec;121:99-117. doi: 10.1016/j.plaphy.2017.10.015. Epub 2017 Oct 25.
The volatile composition of wild strawberry (Fragaria vesca) fruit differs from that of the cultivated strawberry, having more intense and fruity aromas. Over the last few years, the diploid F. vesca has been recognized as a model species for genetic studies of cultivated strawberry (F. x ananassa), and here a previously developed F. vesca/F. bucharica Near Isogenic Line collection (NIL) was used to explore genetic variability of fruit quality traits. Analysis of fruit volatiles by GC-MS in our NIL collection revealed a complex and highly variable profile. One hundred compounds were unequivocally identified, including esters, aldehydes, ketones, alcohols, terpenoids, furans and lactones. Those in a subset, named key volatile compounds (KVCs), are likely contributors to the special aroma/flavour of wild strawberry. Genetic analysis revealed 50 major quantitative trait loci (QTL) including 14 QTL for KVCs, and one segregating as a dominant monogenetic trait for nerolidol. The most determinant regions affecting QTLs for KVCs, were mapped on LG5 and LG7. New candidate genes for the volatile QTL are proposed, based on differences in gene expression between NILs containing specific fragments of F. bucharica and the F. vesca recurrent genome. A high percentage of these candidate genes/alleles were colocalized within the boundaries of introgressed regions that contain QTLs, appearing to affect volatile metabolite accumulation acting in cis. A NIL collection is a good tool for the genetic dissection of volatile accumulation in wild strawberry fruit and a source of information for genes and alleles which may enhance aroma in cultivated strawberry.
野生草莓（Fragaria vesca）果实的挥发性成分与栽培草莓不同，具有更浓郁和水果香气。在过去的几年中，二倍体 F. vesca 已被公认为栽培草莓（F. x ananassa）遗传研究的模式物种，这里使用了先前开发的 F. vesca/F. bucharica 近等基因系（NIL）集合来探索果实品质性状的遗传变异性。我们的 NIL 集合中通过 GC-MS 分析水果挥发物，揭示了复杂且高度可变的图谱。鉴定出 100 种化合物，包括酯类、醛类、酮类、醇类、萜类、呋喃和内酯。其中一小部分，称为关键挥发性化合物（KVCs），可能是野生草莓特殊香气/风味的贡献者。遗传分析显示，包括 KVCs 在内的 50 个主要数量性状基因座（QTL），其中 14 个 QTL 为 KVCs，一个 QTL 为橙花叔醇的显性单基因性状。影响 KVCs QTL 的最决定性区域，映射在 LG5 和 LG7 上。基于包含特定 F. bucharica 片段的 NILs 和 F. vesca 重复基因组之间的基因表达差异，提出了新的挥发性 QTL 候选基因。这些候选基因/等位基因的很大一部分在包含 QTL 的导入区域的边界内共定位，似乎通过顺式作用影响挥发性代谢物的积累。NIL 集合是遗传解析野生草莓果实中挥发性物质积累的良好工具，也是可能增强栽培草莓香气的基因和等位基因的信息来源。
